docs: rework the README for readers adopting the table

[funkadelic]

• Usage and Configuring rewritten for adopters, with the rationale moved to Design notes
• Theming names Style Dictionary and the DTCG tokens
• Testing is split by kind of test, with fallow, Sonar and CodeQL under static analysis, and bundle size moves under Benchmarks
• the getRowId section is corrected
• Internationalization moves under Features, browser support gets its own section, and data attribution moves to the end

---

Summary by cubic

Restructures the README without changing any code: rewrites Usage and Configuring for developers adopting the table, moves the rationale into a new Design notes section, names the Style Dictionary and DTCG token pipeline in Theming, nests Internationalization under Features, gives Browser support its own section, splits Testing into per-kind subsections with fallow, SonarCloud and CodeQL under static analysis, moves bundle size tracking under Benchmarks and data attribution to the end, and corrects the getRowId section to match the implementation.

^{Written for commit 488dd3b. Summary will update on new commits.}

[codecov]

Bundle Report

Bundle size has no change ✅

[codspeed]

Merging this PR will improve performance by 14.59%

⚡ 1 improved benchmark
✅ 26 untouched benchmarks
⏩ 1 skipped benchmark¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	repeat sort of 50250 cities by name (cached)	1,086.8 µs	948.4 µs	+14.59%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

---

_{Comparing docs/readme-theming (488dd3b) with main (e07f467)}

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (e07f467) to head (488dd3b).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #115   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           48        48           
  Lines          773       773           
  Branches       145       145           
=========================================
  Hits           773       773           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

[github-actions]

Lighthouse, median of 3 mobile runs

Page	Score	FCP	LCP	TBT	CLS	Speed Index
Cities	100	1.1s	1.4s	22ms	0.000	1.1s
Films	94	1.1s	3.0s	0ms	0.000	1.1s

Full reports

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud